Hi @meyers66 , there are some major differences between ski helmets and bike helmets so I'm glad that you reached out. In addition to fit, coverage, and warmth differences, the function of the helmet is different too. Bicycling helmets are typically designed for a single impact, meaning that they should be replaced after impact. Helmets designed for skiing and snowboarding, however, take into account that you may have multiple falls in these activities, especially if you are new to the activity. Check out our Expert Advice article for How to Choose a Ski/Snowboard Helmet, which states, "All helmets sold at REI meet the most common U.S.-based standard for snow helmet certification, known as ASTM F2040. That said, when wearing your helmet, remember that they are valuable but not invincible, and any protection they may provide is limited."
I hope you find this information helpful. Happy Skiing!
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